1. Technical Field
The present invention generally relates to motor vehicles and, more particularly, to the connection between powertrain components of the motor vehicle. More specifically, but without restriction to the particular embodiment and/or use which is shown and described for purposes of illustration, the present invention relates to a transfer case with a piloted socket-type mount to a transmission.
2. Discussion
As is known, motor vehicles include a drivetrain comprised of a power generating unit (the engine) and one or more power transmission devices (i.e., transmission, transfer case, axle assemblies, torque couplings, etc.) which are operably interconnected to transfer drive torque to the driven wheels. In the case of four-wheel drive vehicles, one such interconnection occurs between the transmission and the transfer case. Generally, the transmission and the transfer case each include a housing having a flange or end plate extending radially therefrom. As is conventional, each flange includes a plurality of longitudinal apertures. When the housings of the transmission and transfer case are to be interconnected, planar mounting surfaces on the radial flanges are positioned adjacent to one another and the apertures are aligned. Standard fasteners, such as threaded bolts, are installed in the aligned mounting apertures to clamp the radial flanges together, thereby rigidly mounting the transfer case to the transmission.
While a conventional flange mount system for interconnecting the housings of power transmission assemblies have been used successfully, opportunities for improvement still exist. For example, conventional flush-mounted flange connections do not lend themselves to a piloted alignment system. Specifically, radial flange joints typically do not include geometrical features such as pilots or keyways to assist in the alignment of the power transfer devices. Furthermore, joint stiffness is a design factor associated with the use of radial mounting flanges. Heavy power transmission assemblies, such as automatic transmissions and transfer cases, often transfer a bending movement to the flange joint connection. To accommodate such bending movements with only limited acceptable flexure of the joint connection, the radial flanges and portions of the housing adjacent the flanges must be thickened to provide the required joint stiffness and strength. Additionally, because the fasteners are parallel to the transmission centerline in the conventional flange mount system, access to the fastener is often limited and sometimes results in the assembly being lengthened to allow fastener assembly clearance and wrench clearance thereby reducing overall powertrain stiffness. Placing the fasteners perpendicular to the transmission centerline eliminates this problem.
Accordingly, the present invention is directed to overcoming the disadvantages commonly associated with the use of conventional radial flange joints to interconnect a pair of power transfer devices in the drivetrain of a motor vehicle. Therefore, it is an object of the present invention to provide a piloted or socket-type connection between a pair of power transmission devices.
A more particular object of the present invention is to provide a piloted socket-type mount connection between a transfer case and a transmission.
In accordance with the present invention, a socket-type connection is made between the housings of first and second power transmission assemblies. In particular, a first housing has an axial extending pilot flange that is adapted for retention within a receptor flange extending from a second housing. The pilot flange has an outer wall surface adapted to matingly engage an inner wall surface of the receptor flange. Alignment apertures in the receptor flange are alignable with mounting bores in the pilot flange so as to permit the use of threaded fasteners for securing the receptor flange on the pilot flange.
As an additional feature, the socket-type connection can include an axial keyway formed in one of the pilot and receptor flanges which is adapted to receive a complimentary keylug formed in the other of the flanges.
Additional benefits and advantages of the present invention will become apparent to those skilled in the art to which this invention relates from a reading of the subsequent description of the preferred embodiment and the appended claims, taken in conjunction with the accompanying drawings.